Need help with the following problems thanks. Charles' and Boyle's law.?

A gas 'X' at 33 degree Celsius is heated to 127 degree celsius at constant pressure. Calculate the percentage increase in the volume of the gas.

Before heating: V₁ = V, T₁ = (273 + 33) K = 206 K
After heating: V₂ = ?, T₂ = (273 + 127) K = 400 K

For a fixed amount of gas at constant pressure :
V₁/T₁ = V₂/T₂
Then, V₂ = V₁ × (T₂/T₁)

Volume after heating, V₂ = V × (400/206) = 1.94V
Percentage increase in volume = [(1.94V - V)/V] × 100% = 94%


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A gas 'X' is collected over water at 17 degree celsius and 750 mm pressure. If the volume of the gas is 50cc, calculate the volume of dry gas at STP. (at 17 degree celsius the vapour pressure is 14mm).

Gas collected over water: P₁ = (750 - 14) mmHg = 736 mmHg, V₁ = 50 cc, T₁ = (273 + 17) K = 298 K
Dry gas at STP: P₂ = 760 mmHg, V₂ = ? cc, T₂ = 273 K

For a fixed amount of gas :
P₁V₁/T₁ = P₂V₂/T₂
Then, V₂ = V₁ × (P₁/P₂) × (T₂/T₁)

Volume of dry gas at STP = (50 cc) × (736/760) × (273/298) = 44.4 cc

V and T are directly proportional .. if absolute temp doubles then the volume will double
33C = 306K ... 127C = 400K
% increase is (94/306) X 100 <<< use a calculator
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P(gas x) = 736 mm Hg
(PV/T)(1) = (PV/T)(2)
(736)(50)/(290) = (760)V/(273)
V = [(273)(736)(50)] / [(290)(760)] <<< use a calculator